What’s mud got to do with it?


I grew up between the Great Lakes and the Finger Lakes, and for the first two decades of my life my perception of lakes was probably similar to that of most other people: lakes were lovely to look at, an ideal spot to build a house, restaurant, or vineyard, perhaps a place to go boating or swimming on a sweltering summer afternoon. But the muck at the bottom? I never thought twice about it.

It turns out that mud can tell stories. Hidden in that sticky matrix of clay, silt, sand, and organic goo are clues to the past. Those clues provide valuable information to scientists like myself. Paleolimnology is a multi-disciplinary field that endeavours to reconstruct the history of lakes and other inland water bodies, often in relation to regional paleoclimate or (pre-) historic events. To do so, researchers can analyse a range of geological, chemical, and biological characteristics of sediment cores that help tease out ancient tales of environmental change. My own work has focused on environmental and hydrologic changes in Cambodia, including the ancient city of Angkor, over the last two millennia.

Lake sediments haven’t often yielded headline-grabbing findings (though political satirist and comedian Stephen Colbert did place the Journal of Paleolimnologyon notice” in 2006). But, paleolimnology’s obscurity is fading. Lake mud can do more than tell stories about the past; it can be a potent tool for protecting our future, as well.

In 2000, a piece of environmental legislation called the EU Water Framework Directive (WFD) was enacted. Essentially, this law tasks EU counties with restoring all their water bodies to “good status” by 2015. But, how do we know what a “good status” might be for a particular body of water? That’s where paleolimnology comes in. Lake sediment records can provide an indication of a baseline, or reference condition, which can be used to achieve restoration targets such as those set out by the EU WFD. Much of this research was carried out within Euro-limpacs, a project set up to help understand how climate change affects aquatic ecosystems. The results generated by Euro-limpacs (which ended in 2009) and its successor REFRESH are useful for implementing not only EU legislation like the WFD, but other multilateral environmental agreements as well, such as the Ramsar Convention and the UN Convention of Biological Diversity.

Paleolimnology also plays a role in assessing ecosystem services. Ecosystem services are the benefits human derive from the environment, which includes resources like food and water, processes such as nutrient cycling, as well as other assets like aesthetic value. Earlier this month, TEEB (The Economics of Ecosystems and Biodiversity) released a report that examined ecosystem services related to water and wetlands. The report reiterates water’s critical importance to human well-being, but also stresses that water-related ecosystem services need to be incorporated into water management strategies around the world.

How can mud help address this? Lake sediment records can preserve signals related to a number of ecosystem services, such as water quality, air quality, plant diversity, or soil stability. Recently, a group of researchers from the Ecosystem Services and Poverty Alleviation (ESPA) programme developed a regional index of ecosystem services from lake records from the Lower Yangtze Basin in China. This index, the first of its kind, tracks the status of certain ecosystems services in the area for the last 200 years. Official records and long-term data collection related to ecosystem services don’t always exist, especially in less-developed countries. Thus, tools like this index, which can provide an alternate source of information about ecosystem services, are incredibly useful to policy and decision makers and are a valuable addition to water management strategies.

The application of paleolimnology to environmental protection and water resource management is still very much in its early days. Even so, mud has already shown its potential to help address some of the more pressing challenges we face today. Never underestimate what you might accomplish by messing about in the (lake) muck.

*Mary Beth Day [2009] is doing a PhD in Earth Sciences. Picture credit: http://www.freedigitalphotos.net and J. Frasse.


Rethinking the maternal bond


In employing the term ‘maternal’ we are often referring to a ‘maternal instinct, ‘bond’ or ‘relationship’ – this last being my intended use. A quick Internet search reveals the maternal relationship to be a bond between a mother and her child. The relationship is typically thought to be continuous in its development, with its foundation beginning in pregnancy and childbirth.

The maternal relationship is an important one. We need only look to examples of other non-human animals (mammals, amphibians, birds, fish, reptiles, invertebrates, etc) to understand its importance, if nothing else, for survival. Think of, for instance, the elephant mother. After 22 months of pregnancy she gives birth to a baby elephant: blind and dependent. The biological mother and the other female elephants in the group, called ‘allmothers’, care for the child until it can care for itself. For humans, the maternal relationship has been shown to lay the groundwork for social, emotional and cognitive development. As such, the maternal relationship has often been accorded a certain sacred status in society.

As the use of assistive reproductive technologies (ARTs), and the practice of adoption, proliferate, they challenge our existing conception of the ‘maternal relationship’, forcing us to re-visit our assumptions and re-engage with our existing conceptions.

ARTs are technologies that assist in achieving and monitoring a pregnancy – one of the most common being in vitro fertilisation (IVF). The use of egg donors means that intended mothers can now carry babies that are not their own genetic child; in addition surrogates can carry an intended mother’s genetic child (gestational surrogacy) or non-genetic child (traditional surrogacy). Surrogacy arrangements, in particular, challenge our conception of the maternal relationship as a bond with its foundations in pregnancy and childbirth.

Partially an attempt to protect this birth mother-child bond, in the UK when a surrogate gives birth she has an absolute right to change her mind. In the past 20 years, however, there have only been two reported cases of surrogates seeking to keep the baby that was not theirs. Studies on the experience of surrogate mothers have largely found that surrogates do not possess an overwhelming maternal bond with the child they carry. In my own research speaking with egg donors and surrogates, many women describe themselves as partakers in the process of helping intended parents achieve their goal of a baby, not as possessing a maternal bond with the child. Importantly, surrogate or adoptive children are able to have strong maternal bonds with their non-birth mothers. The maternal relationship is then perhaps not as dependent on the biological (pregnancy and childbirth) basis as its definition suggests.

The use of ARTs is also contributing to a growing number of single and same-sex parents. If the maternal bond is as sacred as the status it has been accorded, then what of the children of, for instance, same-sex male partners? (And on that note, what of the children raised solely by their father for various reasons, including maternal death?) Are they all emotionally and cognitively deprived? The answer is no. Perhaps this is because the paternal bond can substitute as a replacement for the maternal bond. Or, perhaps the maternal relationship (or at least elements of this relationship) is not limited to one between a child and the female sex.

Returning to the example of non-human animals, let us look for instance at the example of Marmosets – Marmoset fathers lick their newborns as their mother recuperates from the pregnancy, and then feed and carry them. Other examples include male penguins that watch over the fertilised eggs, going months without food, or the Hardhead catfish that carries around fertilised eggs in his mouth also foregoing meals. Facets of these relationships – nurturing, caring, gentleness, and being the prime caregiver – are all qualities attributed to the maternal relationship. When we speak of the maternal relationship we are perhaps referring to a set of traditionally feminine characteristics that are in fact possessable by both male and female. If that is the case, then a maternal bond is thus not necessitated by the relationship between a child and a particular biological sex: female.

It is important to clarify that I am not arguing that the maternal relationship does not hold extraordinary meaning. To do so would be to disregard a history of evidence of its importance among humans and non-humans. Most importantly, it would disregard the significant relationship that many women – as the primary caregivers – develop with their children. This is not my intention.

My wish is to highlight how the rising use of ARTs is re-shaping our existing framework of reproduction and parenthood. The use of ARTs is providing new sociological evidence that challenges the existing conception of the maternal relationship as having a basis in biology. Whether this will have a positive or negative impact is yet to be seen.

*Katie Hammond [2011] is doing a PhD in Sociology at the University of Cambridge, having completed an MPhil in Multi-Disciplinary Gender Studies. This article was first published on the Mapping Maternal Subjectivities, Identities and Ethics blog. Photo credit: Stuart Miles and http://www.freedigitalphotos.net.


Why aren’t you married yet?


After the Chinese New Year, I will officially become a 30-year-old woman. Chinese New Year used to be a fun-filled time: having endless food, visiting relatives, and hopefully, at my age, still getting red envelopes (with money inside, of course!) However, ever since I started to be asked questions like “When are you going to get married?” (after I get my PhD), or “When are you going to finish you PhD?” (you will get a more precise answer from my supervisor), I feel fairly reluctant to see my relatives and less joyful during this festive season. Why has my marital status become a kind of illness for which everyone either feels sympathy or annoyance because of the impression that I am not taking responsibility for my life? With this question in mind, I started my PhD project on investigating Taiwanese people’s marital expectations.

Marriage in East Asian societies used to happen at an early age and was universal. Yet, nowadays, marriage tends to occur during an individual’s late 20s or early 30s. Last year, the mean age for marriage in Taiwan was 31.8 for males and 29.2 for females (see, I am only a bit above the average!). The delayed timing in marriage contributes largely to the lowest fertility rates among many East Asian societies. We hear people saying that late marriage is due to the fact that women are becoming more economically independent and more individualistic (or selfish in terms of wanting to enjoy their single life without the burden from family for a longer period of time). Yet this only explains a very tiny piece of the whole picture. Looking at the survey results, we found that more than 80% of the population still expects to get married at a certain point in their lives. What is keeping them away or postponing them from doing so is more complicated and results from factors founded in both micro-individual situations and macro-social environments.

People in different age groups provide different reasons for why marriage is not an option for them at that life stage. “Too early” and “still in education” are the two most common answers from individuals in their early 20s. As people move into their late 20s, they start giving responses about their continuing single status which reflect more economic concerns, such as “not having got a stable, long-term job”. When they reach their 30s, “having not met someone suitable” takes precedence over the other reasons. These responses depict three important signs of late marriage: first, the expected timing of marriage has been postponed to the late 20s partly due to the prolonged time modern people spend in educational institutions; second, their reasons for not being able to get married change along with the development of different life stages, and third, nowadays it takes longer for young adults to achieve the traditional adulthood markers in terms of attaining economic independence. The term “emerging adulthood” has been coined to describe these younger cohorts, many of whom are stuck in between adolescence and adulthood and struggle to establish their adulthood identities.

Studies on marital timing in the region have so far paid exclusive attention to women’s marital timing. Yet gender is like a coin with two sides. When there are women postponing the timing of their marriage, there are going to be men doing the same (this may be different if civil partnership without limitations to just heterosexual couples becomes universal). While scholars have argued that the patriarchal tradition in these societies, which requires women to be submissive to their husband and sacrifice their careers for their families after marriage, has meant many younger women see marriage in an unfavourable light, the economic requirement on men from this traditional ideology has made it equally difficult for men to make the commitment.

Last December, in the space of one month I attended four weddings of friends around my age. This somehow signals that marriage has not been totally abandoned (or I am about the age to get married) but just happens a bit later. Next time, instead of questioning someone about when he or she intends to get married, why not be patient and just wait for their wedding invitations to surprise you or toast to their bravely-chosen forever singleton status?

*Yen-Chun Cheryl Chen [2010] is currently a PhD student studying Sociology. Picture credit: Danilo Rizzuti and http://www.freedigitalphotos.net

Die another day – when biology becomes a crime hunt


I am a PhD student in Pharmacology. As I learnt over the past year, this can be a pretty good conversation killer. Except if people misunderstand you and are suddenly dying to know more about your project in “Farm Ecology”. Blame it on my French accent. After several social interaction disasters, I couldn’t help but wonder what is it in Pharmacology that puts people off?

If I refer to the etymology, Pharmacology comes from the Greek word pharmakon, which means poison, and logia, meaning study of. I can see that the study of poisons might sound a bit scary indeed. More realistically though, Pharmacology is the intersection of several areas of study. It connects physiology, pathology, chemistry, cellular and molecular biology, toxicology and many others. In an era of interdependent fields, Pharmacology is at the very centre.

My interest focuses on the role of P2X7. As much as it might sound like a super-secret-mission code, P2X7 is simply the name of a cellular receptor activated by the energy currency of the cell (ATP). The secret of P2X7 lies in its versatile ability to promote cellular death as well as growth. Whether we talk about cancer, inflammation, fibrosis, pain or diabetes, P2X7 seems to be part of the show. Actually, P2X7 sounds very much like the James Bond of the cell – although somewhat less sexy than Pierce Brosnan. And with this statement comes my first question: where is P2X7?

P2X7 has been found in different cell types, but predominantly in cells involved in the immune system. It is not so surprising to find the agent number 7 on the crime scene, but whereabouts exactly? Is it kindly waiting for its time in the antechamber (also known as endoplasmic reticulum for the biologists out there) or up front on the balcony (that would be the plasma membrane, for the enlightened)? And that is where the mystery kicks in. P2X7 has been found at the plasma membrane, aka the balcony. The receptor is structured as a channel through the plasma membrane, and in the presence of ATP, it will open and let ions pass through, allowing exchange between the extracellular and the intracellular environment. If the interaction with ATP is prolonged, the receptor dilates into a bigger pore, letting bigger molecules pass through and irreversibly leading to the death of the cell. However, P2X7 is not always at the plasma membrane but can be retained in the endoplasmic reticulum.

So what is the order that our Agent 7 needs to leave the antechamber for the balcony?

One of the particularities of P2X7 is its uniquely long intracellular tail. This James Bond accessory has been shown to be crucial for its mission assignment. A few tweaks to it and Agent 7 will lose itself in the kitchen or the dining room. Could it be that this accessory is the secret of P2X7? To answer this question, I transferred this accessory to an innocent cell character present in immune cells, and thus created what we call a chimera – a random someone with the James Bond accessory. This chimera allows me to study the properties imparted by the intracellular tail of P2X7. By doing so, it not only allows me to understand how to communicate with and assign my cellular James Bond to missions, but also what Bond needs to succeed. Surely, everyone will agree that James Bond would not be James Bond without his Bond Girls. And that is my next question: who is the James Bond Girl?

There are plenty of attractive molecules out there willing to interact with James Bond, and the hypothesis that the charm of the famous Agent 7 lies in its intracellular tail has been mentioned more than once. My chimera represents then a way to trap James Bond Girl candidates. I can meet the girls and ask them what it is that is so irresistible in P2X7.

Surely, all the mysteries of James Bond are far too complex to be fully understood, but the end of our crime hunt might well be the discovery of a tool that will allow us to make cells die another day.

*Marie Brunet [2011] is doing a PhD in Pharmacology. Picture credit: Dream designs and http://www.freedigitalphotos.net.